脾失健运膏脂转输障碍对HDL亚类代谢及胆固醇逆向转运的影响

Dyslipidemia is an important risk factor for atherosclerosis (AS) and Traditional Chinese Medicine believes that spleen deficiency and Gaozhi transportation and transformation dysfunction is one of key pathogenesis of dyslipidemia. A direct anti-atherogenic role of serum high-density lipoprotein (HDL) has been mainly attributed to the role that they play in the reverse cholesterol (RCT). The nascent discoidal preβ-HDL subclasses are converted to mature spherical HDL2 subclasses, following the route of preβ1-HDL→HDL3→HDL2 during the process of RCT. Our previous studies have demonstrated that small-sized HDL subclasses significantly increased while large-sized HDL subclasses significantly decreased in hyperlipidemic subjects.When spleen deficiency and Gaozhi transportation and transformation dysfunction occurs, RCT might be weakened and HDL maturation might be abnormal, which might be the one of the pathological basis of AS associated disease Therefore, this project is conducted to investigate the change of HDL subclasses metabolism and distribution in the population and rats suffering spleen deficiency and Gaozhi transportation and transformation dysfunction. Furthermore, cholesterol efflux-related genes in macrophages cell and cholesterol intake-related genes in liver cells will be studied. Our work may contribute to reveal the key regulation mechanism in lipid metabolism for the theory of spleen governing transportation and transformation in HDL subclasses level and provide the molecular biological evidence for clinical treatment in hyperlipidemia based on the spleen.

血脂异常是动脉粥样硬化（AS）的重要危险因素,中医认为脾失健运膏脂转输障碍可导致血脂异常。高密度脂蛋白(HDL)主要通过胆固醇逆向转运（RCT）发挥抗AS作用，并借此完成HDL亚类的成熟递变。脾失健运膏脂转输障碍，RCT受阻，HDL亚类成熟代谢异常，这可能是AS性疾病发生发展的微观病理基础之一。课题组前期已证实高脂血症患者血清HDL亚类组成、分布异常，RCT减弱。本项目拟分别以脾虚高脂血症临床病例以及大鼠模型为研究对象，从HDL亚类和RCT途径入手，运用实时定量RT-PCR、流式细胞术、非变性双向梯度电泳-免疫印迹等技术，观察脾失健运膏脂转输障碍对HDL亚类代谢以及RCT最关键的两个环节-巨噬细胞胆固醇流出、肝细胞胆固醇摄取的影响及机制，并探讨健脾降脂中药的干预作用及效应机制。研究将从HDL亚类水平揭示"脾主运化"功能在脂质代谢中关键调控机制，为临床"从脾论治"血脂异常提供分子生物学依据。

血脂异常是动脉粥样硬化（AS）的重要危险因素，中医认为脾失健运膏脂转输障碍可导致血脂异常。高密度脂蛋白(HDL)主要通过胆固醇逆向转运（RCT）发挥抗AS作用，并借此完成HDL亚类的成熟递变。脾失健运膏脂转输障碍，RCT受阻，HDL亚类成熟代谢异常，这可能是AS性疾病发生发展的微观病理基础之一。课题组前期已证实高脂血症患者血清HDL亚类组成、分布异常，RCT减弱。本项目分别以脾虚高脂血症临床病例以及大鼠模型为研究对象，从HDL亚类和RCT途径入手，运用实时定量RT-PCR、PCR array、Western blotting、流式细胞术、透射电镜、非变性双向梯度电泳—免疫印迹及Lipoprint脂蛋白分析等技术，观察脾失健运膏脂转输障碍对HDL亚类代谢的影响及机制，并探讨健脾降脂中药的干预作用及效应机制，进一步拓展性地分析了大鼠血清低密度脂蛋白亚类分布特征，探讨了脾虚状态高脂血症大鼠肝miRNA-122a的表达及其与SREBP-2通路调控的关系。临床试验研究发现，单纯高脂血症及高脂脾虚患者血浆HDL颗粒直径均呈变小趋势，后者变化程度更加明显。动物实验结果显示，脾虚高脂大鼠血清TC、LDL-C水平显著升高，HDL-C、AMY及尿D-木糖排泄率显著降低，血清大颗粒HDL含量降低，中颗粒HDL含量增加，肝脏形成大量脂质沉积，肝细胞萎缩明显，肝脏CYP7A1、LDL-R、SREBP-2基因表达显著降低；治疗组大鼠血清TC、LDL-C水平显著降低，HDL-C水平及AMY活性显著升高，同时尿D-木糖排泄率显著升高，血清大颗粒HDL含量增加，中颗粒HDL含量降低，肝脏脂滴及空泡减少，肝脏CYP7A1、LDL-R、SREBP-2基因表达显著升高。研究从HDL亚类水平揭示“脾主运化”功能在脂质代谢中关键调控机制，为临床“从脾论治”血脂异常提供分子生物学依据。本项目已发表论文24篇，录用待发表论文4篇，其中SCI收录论文2篇，出版著作1部，获批发明专利2项，实用新型专利3项，培养研究生3人。